44 points explain what does "by" mean in math

Jamie went to home depot.she bought 25 bags of soil that cost $9 per bag.she bought 15 pots at $8 each, and she bought 23 bags of pebbles at $15 each.she used a coupon that gave her $5 off for every 100 dollars she spent. how much did jamie pay at the end?

When using the linear combination metho e linear combination method to solve a system of linear equations, the four options are:

Acircle has a circumference of 28.36 units what is the diameter of the circle